JP3164683B2 - Ultrasonic motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic motor, and more particularly, to an ultrasonic motor which is rotated by vibration generated by an electromechanical energy conversion element.

[0002]

2. Description of the Related Art Various ultrasonic motors that rotate by vibration generated by an electro-mechanical energy conversion element have been proposed in the related art.
-91668. The vibrator described in this publication is formed such that the outer diameters at both ends thereof are larger than the outer diameter at the node position in the driving vibration mode. By forming the shape of the vibrator in this way, it is possible to reduce the natural frequency as compared with a vibrator with a uniform diameter, and to increase the modal mass significantly and obtain a large vibration amplitude Can be done. By using such technical means, the motor efficiency including the circuit system for driving the motor is improved and the driving is stabilized.

As another technical means for obtaining the same effect as described above, Japanese Patent Laid-Open Publication No. Hei.
No. 91670 is proposed. In this technical means, in order to apply a voltage to a piezoelectric element of a Langevin type ultrasonic transducer, a thin metal plate is formed in substantially the same shape as the piezoelectric element to form an electrode plate, and a lead wire is connected from this electrode plate. Such electrode plates are fixed to both end faces of the piezoelectric element, and such a configuration is generally used as voltage applying means. Such a voltage applying means has been widely used for a long time because it is easy to manufacture and has good adhesion to the piezoelectric element.

[0004]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 4-916 is disclosed.
Japanese Patent Application Laid-Open No. 68-68, No. 68, discloses a technique in which a large-diameter portion is disposed at an antinode of vibration to increase the vibration amplitude, which is very often used. There is a concern that the weight may be increased. If the outer circumference of the additional mass is made larger with respect to the outer diameter of the piezoelectric element, which is an electro-mechanical energy conversion element, the size becomes larger in the radial direction, while if the additional mass is made longer in the axial direction, The overall length of the vibrator becomes large. Ultrasonic motors using such transducers are not very problematic when used in areas where there is a relatively large amount of space, but they are a major drawback when used in confined spaces. Can not.

Further, as shown in the above-mentioned Japanese Patent Application Laid-Open No. Hei 4-91670, when the high-density portion is used at the antinode of vibration, the size can be reduced, but members of two different materials are required. Also, there is a problem that the cost is increased due to an increase in the number of steps for assembling the plurality of members.

On the other hand, the above-described voltage applying means has a space problem because the terminal portion of the electrode plate protrudes from the outer diameter of the ultrasonic vibrator. Further, when the piezoelectric elements are stacked in multiple layers, in addition to the large number of terminal portions protruding on the outer periphery of the ultrasonic vibrator, the number of lead wires connected to these terminal portions also increases, further increasing the space. The problem gets bigger. Needless to say, the wiring becomes complicated. These are particularly small ultrasonic motors (eg, φ
This is an important problem in an ultrasonic motor of 10 (mm) or less.

The present invention has been made in view of the above problems, and has as its object to provide a small-space ultrasonic motor capable of improving the efficiency by increasing the vibration amplitude.

[0008]

In order to achieve the above object, a first ultrasonic motor according to the present invention comprises a rod-shaped electro-mechanical energy conversion element, and the electro-mechanical energy conversion element comprises :
A vibration generating unit that rotates while the end face is inclined with respect to the central axis by applying an electric signal to the energy conversion element ,
It is provided coaxially adjacent to one end face of this vibration generation part .
Which is formed in the connecting portion of the resonator element having a groove on a side surface, and the resonator element and the vibration generating portion, the resonance frequency of the vibration generating portion
A full <br/> flange portion in the shape of the resonance frequency of the number of the resonator element is matched, it is pressed against the vibrating element, characterized in that anda driven member is moved in a predetermined direction . Ma
Further, in order to achieve the above object, the second aspect of the present invention
Ultrasonic motors are rod-shaped electro-mechanical energy conversion elements
And providing an electric signal to the electro-mechanical energy conversion element.
The end face is tilted with respect to the center axis by applying
Vibration generator that rotates and one end of the vibration generator
Provided coaxially adjacent to the surface and divided into multiple parts around the axis
A vibrating reed having a groove on the side surface, and the vibrating reed
A flange portion formed at a connection portion with the vibration generating portion,
Driven part pressed by the vibrating piece and moved in a predetermined direction
And a material. In addition, the above eye
Third ultrasonic motor according to the present invention to achieve
Comprises a rod-shaped electro-mechanical energy conversion element,
Applying an electrical signal to the gas-mechanical energy conversion element
Causes the end face to rotate while tilting with respect to the central axis
Vibration generating part, adjacent to one end face of the vibration generating part
A vibrating reed provided coaxially and having a groove on the side face;
The central axis is provided at a connection portion between the piece and the vibration generation portion.
A thin wall is formed on both the plane parallel and
Edge part and pressed by the vibrating piece and moved in a predetermined direction.
And a driven member.

[0009]

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of the present invention. In the first embodiment, a piezoelectric element in which silver is deposited on a voltage application surface is used as an electro-mechanical energy conversion element.

FIG. 1 is a side view showing the entire ultrasonic motor showing the right half in cross section from the central axis, and FIG. 2 is an exploded perspective view showing the laminated piezoelectric elements stretched in the central axis direction. . The ultrasonic motor according to the first embodiment includes a piezoelectric element 1, 2, 3,
The amount of pressure applied to the rotor 13 as a driven member by a nut 21 via a disc spring 20 is placed on a vibrator 19 formed by sandwiching the oscillator 5 composed of a member 4 between the first resonator 9 and the second resonator 17. The screw is adjustably screwed to form the main part.

The oscillator 5 includes an electrode plate 8, a first piezoelectric element 1, an electrode plate 6, a second piezoelectric element 2, an electrode plate 8, a third piezoelectric element 3, an electrode plate 7, a fourth piezoelectric element 4, The plates 8 are laminated in this order. The donut-shaped first piezoelectric element 1, the second piezoelectric element 2, the third piezoelectric element 3, and the fourth piezoelectric element 4 are each polarized in a direction perpendicular to the central axis. The polarization direction of the third piezoelectric element 3 and the polarization direction of the fourth piezoelectric element 4 are also reversed. Then, the polarization axes of the third piezoelectric element 3 and the fourth piezoelectric element 4 are arranged to be shifted by 90 ° from the polarization axes of the first piezoelectric element 1 and the second piezoelectric element 2.

The electrode plates 6, 8, and 7 are made of copper, and the electrode plates 6 and 7 are provided with a sinusoidal voltage near the resonance frequency, which is 90 ° out of phase (for example, a voltage applied to the electrode plate 6). Is s
In ωt, a voltage having a waveform of cos ωt is applied to the electrode plate 7 from a drive circuit (not shown), and the electrode plate 8 is connected to the ground (indicated by the symbol G in the figure).

The first resonator 9 is made of a material having excellent vibration transmission (aluminum alloy, stainless steel, phosphor bronze, duralumin, titanium alloy, etc.). hand,
The hardness is set to 800 or more. A female screw 11 to be screwed with the fastening member 10 is engraved on the center axis portion of the first resonator 9, and is directed from the end face of the vibrator 19 toward the voltage elements 1, 2, 3, and 4. A cup-shaped recess 12 is formed so that the end face of the first resonator 9 does not contact the fastening member 10. Therefore, the vicinity of the contact portion of the first resonator 9 with the rotor 13 is formed in a thin cylindrical shape, and constitutes the resonator element 23. Then, a portion below the resonator element 23, that is, a lower portion of the first resonator 9, and the oscillator 5
And the second resonator 17 constitute the vibration generating unit 24. Further, on the outer peripheral surface of the first resonator 9, a first peripheral groove 14 and a second peripheral groove 15 having a predetermined depth are engraved concentrically with the outer periphery. At this time, the portion connecting the second peripheral groove 15 and the peripheral surface of the resonator 9, that is, the vibrating piece 23 and the vibration generating section 2
A thin-walled flange portion 16 is formed at a portion connecting the first and second flanges 4.

The second resonator 17 disposed on the other end face of the piezoelectric elements 1, 2, 3, 4 is also formed of the same material as that of the first resonator 6, and has a central shaft portion. Is provided with a female screw 18 for screwing with the fastening member 10.

As shown, each of the piezoelectric elements 1, 2, 3, 4
The electrode plates 6, 7, and 8 are sandwiched between the first resonator 9 and the second resonator 17 in a state where the electrode plates 6, 7, and 8 are penetrated by bolts having two screw portions, which are the fastening members 10, so that the components After applying an epoxy-based adhesive, the adhesive is cured and the adhesive is cured to form the ultrasonic vibrator 19.

The bolt 10 forms an ultrasonic vibrator 19 by pressure bonding and supports a rotor 13 having a pressing mechanism on an end face of the ultrasonic vibrator 19. In this embodiment, a pressing mechanism that can change the amount of pressure of the disc spring 20 by the nut 21 is used.

In the present embodiment, the rotor 13 is made of an aluminum alloy, and its sliding portion is subjected to oxalic acid alumite treatment. The rotor 13 has a circumferential groove 22 engraved slightly below the circumferential surface thereof, and a lower surface side of which is a flange portion 22a. Then, the rotor 13 temporarily forms a thin peripheral surface downward from the flange portion 22a, and then returns to the inward flange portion 2 again.
2b is formed, and the lower part thereof is a contact part 2 with the vibrator.
2c. With such a configuration, the rotor 13
The natural frequency of the contact portion is set to be higher than the drive frequency of the ultrasonic vibrator 19.

The operation of the first embodiment will be described.
When a sine wave voltage near the resonance frequency whose phase is shifted by 90 ° from each other is applied to the electrode plates 6 and 7, a bending vibration that rotates around the central axis is generated in the vibration generating unit 24. Therefore, an elliptical motion that rotates around the central axis is generated on the end surface of the vibrating reed 23, and the rotor 13 that is pressed and installed is rotated. When the phase difference between the drive voltages applied to the electrode plates 6 and 7 is shifted by 180 °, an elliptical motion of reverse rotation is generated in the ultrasonic transducer 19, and the rotor 13 is rotated reversely.

FIG. 3 is a cross-sectional view of a half of the first resonator 9 showing a state when the ultrasonic vibrator 19 performs bending vibration.
The bending vibration generated by the vibration generating section 24 is transmitted to the resonator element 23 via the flange section 16. At this time, the length l and the thickness t of the flange portion 16 are adjusted so that the resonance frequency of the bending vibration of the vibrating reed 23 matches the resonance frequency of the bending vibration of the vibration generating section 24. Since the flange portion 16 has a thin structure, it has a spring characteristic and strongly excites the vibrating reed 23. Due to this action, the small vibration amplitude of the vibration generating section 24 is, for example, an amplitude magnified several tens times on the end surface of the vibrating piece 23 (that is, the contact surface with the rotor 13).

FIG. 4 is a graph showing the relationship between the thickness t of the flange portion 16 and the vibration amplitude. As shown in the figure, the vibration amplitude is such that the thickness of the flange portion 16 is t = 0.225 (mm).
, The resonance frequency becomes the lowest at this time. In order to rotate the motor with relatively high efficiency, the thickness of the flange portion 16 is set to 0.1 (mm) to 0.4 (mm).
In this case, the rotation of the rotor 13 is also stable. On the other hand, when the thickness of the flange portion 16 is 0.
If it is less than 1 (mm) or exceeds 0.4 (mm), the vibration amplitude becomes extremely small, the efficiency of the motor is reduced, and heat generation becomes severe.

According to the first embodiment, the resonator element 2
A large amplitude bending vibration is excited on the end face of the rotor 3 and the rotor 13 can be rotated stably. Further, since the resonance frequencies of the vibrating reed 23 and the vibration generating section 24 are accurately matched, the most efficient enlargement is performed and the motor can be made highly efficient. Further, the resonator element 23
Since the resonance frequency is dependent on the shape of the flange portion 16, it is not necessary to adjust the size of the resonator element 23, and the ultrasonic transducer can be downsized. Thus, a small and highly efficient ultrasonic motor can be obtained.

FIG. 5 shows a second embodiment of the present invention. In the second embodiment, since the resonator element in the first embodiment is divided into four parts, description of the same parts as in the first embodiment will be omitted, and only different parts will be described.

As in the first embodiment, the first resonator 9 has a cup-shaped recess 12, a first circumferential groove 14, and a second circumferential groove 1 as in the first embodiment.
5, a flange portion 16 is formed. The first resonator 9 has four grooves 25 divided into four in the circumferential direction.
Are formed at a predetermined depth parallel to the central axis from the direction in which the rotor 13 (see FIG. 1) is provided to the direction of the piezoelectric elements 1, 2, 3, and 4. That is, the resonator element 23
Is divided into four parts along the circumferential direction.

The operation of the second embodiment configured as described above will be described. Since the regulation of the radial movement of the vibrating reed 23 is greatly eliminated, the vibrating reed 23 vibrates greatly. At this time, the shape of the flange portion 16 is adjusted so that the resonance frequency of the vibration generating portion and the resonance frequency of each vibrating piece 23 are the same as in the first embodiment.

According to the second embodiment, the same effects as those of the first embodiment are obtained, and a larger vibration amplitude is generated on the end surface of the vibrating piece. Is obtained.

FIG. 6 shows a third embodiment of the present invention. Since the third embodiment is a modification of the shape of the flange portion in the first embodiment, the description of the same parts as those in the first embodiment will be omitted, and only different parts will be described.

As shown in the figure, the flange portion 26 of the third embodiment is formed so as to have an L-shaped cross section. That is, after the thin vertical flange portion 26a once rises vertically from the lower portion of the first resonator 9 along the axial direction, the thin horizontal flange portion 26b is formed outwardly perpendicular to the axis. .

As described above, the shape of the flange portion formed on the first resonator is not limited to the thin shape formed perpendicular to the axis, but may be any shape that resonates the resonator element using the spring characteristics. For example, it is possible to realize a function of increasing the vibration amplitude with respect to those having a wide range of shapes. As a configuration having such a spring characteristic, for example, a configuration as shown in FIG. In the structure shown in FIG. 7, the upper end surface of the flange portion is formed in a tapered shape directed downward, and the thinnest portion is provided at one location indicated by reference numeral 27, and this portion has spring characteristics. It is what was constituted.

The operation of the third embodiment thus constructed is substantially the same as that of the first embodiment, except that the vibration generator 2
When transmitting the vibration generated from 4 to the resonator element, the above-described flange portion 26 bends in both directions parallel to the central axis and in a direction perpendicular to the central axis to increase the amplitude.

According to the third embodiment, the same effects as those of the first embodiment can be obtained even with a shape other than the thin flange portion, the vibration amplitude can be increased, and the vibration amplitude can be stabilized. It can be a rotating ultrasonic motor.

FIGS. 8 to 11 show a fourth embodiment of the present invention. In the fourth embodiment, a piezoelectric element 51 in which silver is deposited on a voltage application surface is used as an electro-mechanical energy conversion element. FIG. 8 shows thin electrode plates 52 and 5.
9 is a side view showing a cross section of the right half of the ultrasonic motor in which the piezoelectric elements 3 and 54 are incorporated. FIG.
FIG. 10 is an exploded perspective view of the flexible substrate 55 as a voltage supply member.
And FIG. 11 is an enlarged cross-sectional view showing a connection part.

The ultrasonic motor of this embodiment has an ultrasonic vibrator 56 and a rotor 58 pressed by pressing means 57 against the ultrasonic vibrator 56. The above ultrasonic transducer 5
6, a plurality of piezoelectric elements 51 are laminated, and thin electrode plates 52, 53, 54 for applying a voltage to a voltage application surface are provided between the respective layers of the piezoelectric elements 51 and on both end faces. Have been. These thin electrode plates 52, 53, 54
As shown in FIG.
9 are protruding. The electrode plates 52, 53, 54 are made of, for example, phosphor bronze having a thickness of 50 (μm), and the surfaces thereof are nickel-plated. Electrode plates 52, 5
As shown in FIG. 10, the joining portion 59 formed so as to protrude from the third and 54 is bent downward, for example, along the peripheral surface of the ultrasonic transducer 56.

The thin electrode plate 53 has, for example, sin
A voltage having a waveform of ωt, the electrode plate 5
3 and a voltage having a waveform of, for example, cos ωt, which is 90 degrees out of phase, is applied to each of the three thin electrode plates 52.
Is grounded.

A flexible board 55 on which three copper patterns 60 are formed is connected to the above-mentioned electrode plates 52, 53, 54. The flexible substrate 55 is provided with an insulating coating so as to cover the pattern 60, but the distal end portion is not coated with the insulating coating, and is an exposed portion 61 from which the pattern 60 is exposed. The exposed surface of the pattern 60 is plated with nickel. As shown in FIG. 10, such a flexible substrate 55 is curved and adhered along the peripheral surface of the ultrasonic transducer 56.

The thin electrode plates 52, 53, 54 as described above
Of the flexible substrate 55 and the pattern exposed portion 61 of the flexible substrate 55 are connected by ultrasonic bonding with a device such as a wire bonder via a small-diameter wire 62. By this ultrasonic connection, as shown in FIG. 11, the distal end portion of the wire 62 is deformed and alloyed with nickel of the joint portion 59 to be connected. Here, a thin aluminum wire of φ50 (μm) is used as the wire 62. The maximum position height of the wire 62 when such an aluminum thin wire is used is approximately 0.2 (mm). Although not shown, the surface is coated with a phenol resin after connection to protect the small-diameter wire 62.

The operation of the ultrasonic motor as described above is almost the same as that of the first embodiment. That is, the piezoelectric element 51
Is applied, the ultrasonic transducer 56 excites the primary bending vibration, and the bending vibration becomes a motion of rotating around a central axis in a predetermined direction. By this movement, the rotor 58 pressed by the pressing means 57 against the end face of the vibrator 56 is rotated.

According to the fourth embodiment, the ultrasonic bonding is performed by joining the joining portion of the thin electrode plate and the exposed portion of the flexible substrate, which is a voltage supply member, through a thin aluminum wire. The protrusion from the outer periphery of the motor can be reduced. In other words, the area required for the connection can be made very small as compared with the space caused by the swelling of the conventional solder or the like. Even when the above-mentioned protective coating of phenol resin is formed, the amount of protrusion from the outer periphery can be suppressed to approximately 0.5 (mm) or less.

The connecting portion of the small diameter wire by the ultrasonic bonding is very small, and when the diameter of the small diameter wire is d, it is only about 1.5d, that is, about 1.5 times the diameter. That is, the joining portion of the thin electrode plates required for connecting the wires can be made very small. In addition, the aluminum thin wire is firmly connected to the joint portion of the nickel-plated thin electrode plate and the exposed pattern of the flexible substrate by ultrasonic bonding, and is disconnected by ultrasonic vibration of the ultrasonic motor. Never.
Further, according to such ultrasonic bonding, there is an effect that the piezoelectric element is not affected by heat and the piezoelectric characteristics are not deteriorated by heat.

As described above, the protrusion due to the wiring is very small, so that the motor can be downsized. Also, even if the motor is small, the wiring connection work is simplified and the assembling time can be reduced.

FIG. 12 shows a fifth embodiment of the present invention, and is an enlarged perspective view showing a connection portion between a flexible substrate and a thin electrode plate. Since the fifth embodiment is almost the same as the fourth embodiment, only different portions will be described.
A flexible substrate 64 as a voltage supply member is connected to the thin electrode plates 52, 53, 54. The flexible substrate 64 has a tip formed obliquely, and a plurality of copper patterns 60 are formed in accordance with the number of the thin plate electrodes 52, 53, 54. Among these copper patterns 60, the copper patterns connected to the ground are connected to each other in the flexible substrate 64 to be integrated. The flexible substrate 64 is provided with an insulating coating so as to cover the pattern 60, but the distal end portion is not coated with the insulating coating, and the pattern 60 is exposed. The exposed surface of the pattern 60 is plated with nickel. Such a flexible substrate 64 is bonded in a curved shape along the peripheral surface of the ultrasonic transducer 56.

Nickel-plated thin electrode plate 5
As shown in the figure, the joining portions 59 of the members 2, 53, 54 are configured so as to be arranged slightly obliquely in the circumferential direction so as to project obliquely. Further, the joint portion 59 is bent downward, for example, along the outer peripheral side surface of the ultrasonic transducer 56 as in the fourth embodiment.

The obliquely formed distal end of the flexible substrate 64 is arranged in accordance with such a joint portion 59, and each of the joint portions 59 and the copper pattern 60 are ultrasonically joined through a thin aluminum wire 62. Connect with In addition,
As in the fourth embodiment, the protective coating is performed with a phenol resin (not shown) after the connection.

According to the fifth embodiment, since the connection distance of the small diameter wire can be reduced, the maximum height of the small diameter wire can be further reduced. In addition, since the ground is integrated into one in the flexible substrate,
The small diameter wires do not intersect, and the ultrasonic bonding can be performed more easily.

As described above, the amount of protrusion of the small-diameter wire can be further reduced, and the size of the motor can be reduced. in addition,
Since the connection distance is shortened, the reliability of the connection is improved, and the wiring operation can be simplified.

FIG. 13 shows a modified example of the fifth embodiment, and is an enlarged perspective view showing a voltage supply member and a connection portion of a thin electrode plate. In the fifth embodiment, a glass epoxy substrate 6 having a thickness of about 0.1 (mm) is used as a voltage supply member.
5 is used. As shown in the figure, a copper pattern 60 is formed on the glass epoxy substrate 65 by connecting a ground in the substrate. The exposed portion 66 of the copper pattern 60 is formed on the side of the tip of the glass epoxy substrate 65, and the exposed copper pattern 60 is subjected to nickel plating.

In correspondence with the exposed portion 66 of the glass epoxy substrate 65, the joining portions 59 of the thin plate electrodes 52, 53, 54 project in a line parallel to the central axis as shown in the figure, and further downward. It is bent. A glass epoxy substrate 65 is curved and adhered and fixed along the peripheral surface in the vicinity of the joining portion 59, and the joining portion 59 and the copper pattern 60 are ultrasonically joined to each other through the aluminum small-diameter wire 62. Connected. With such a configuration, substantially the same operation and effect as those of the fifth embodiment can be obtained.

FIG. 14 shows a sixth embodiment of the present invention, and is an enlarged perspective view showing a voltage supply member and a connecting portion of a thin electrode plate. Since the sixth embodiment is almost the same as the fourth embodiment, only different portions will be described. In the sixth embodiment, the voltage supply member has a thickness of 0.1 (mm).
Is used.

As shown in the figure, the glass epoxy substrate 67 has a tip portion formed in a shape having a step substantially equal to the interval between the electrode plates, and an exposed portion 68 from which the copper pattern 60 is exposed for each step. The exposed portion of the copper pattern 60 is formed by nickel plating. The copper pattern connected to the ground is provided at the right end and has the longest exposed portion.

Glass epoxy substrate 67 having this step
Corresponding to the shape of the tip of the thin electrode plate 52, 53, 5
Four joints 59 are arranged, and only two of these joints 59 connected to the earth are arranged on the side of the rightmost earth pattern.

The thin electrode plates 52, 53, 54 as described above
Of the glass epoxy substrate 67 and the copper pattern 60 of the exposed portion 68 of the glass epoxy substrate 67 are connected by ultrasonic bonding via a thin aluminum wire 62.

According to the sixth embodiment, the operation and effects are substantially the same as those of the fourth embodiment, and a simple structure can be obtained without having to cross the copper pattern of the glass epoxy substrate inside. Therefore, the cost for manufacturing the substrate can be reduced. Further, similarly to the fifth embodiment, the connection distance of the small-diameter wire can be reduced, so that the protrusion amount can be reduced, and the reliability can be improved.

FIGS. 15 to 17 show a seventh embodiment of the present invention. Since the seventh embodiment is almost the same as the fifth embodiment, only different parts will be described. The thin electrode plates 52, 53, 5 in the seventh embodiment
Reference numeral 4 denotes the shape of the electrode plate 69 shown in FIG. 16, which is pretreated based on phosphor bronze, and is formed in a thin plate shape having a thickness of about 50 (μm) provided with aluminum on the surface. Is provided with a connecting portion 70 protruding in an elongated shape. The electrode plates 52, 53, 54 having such a shape are
As shown in FIG. 15, a voltage supply member is connected to the flexible substrate 64 having the tip end described in the fifth embodiment, which is formed obliquely.

The flexible substrate 64 is bonded and fixed along the peripheral surface of the ultrasonic transducer 56 as shown in the figure. After that, the connecting portion 70 is bent downward along the central axis direction of the ultrasonic transducer 56 so as to coincide with the pattern exposed portion 71 of the flexible substrate 64. FIG.
Shows an enlarged cross-sectional view of such a connecting portion, and a portion where the connecting portion 70 and the pattern exposed portion 71 coincide (that is, a portion indicated by an arrow 72) is ultrasonically bonded.

According to the seventh embodiment, since the ultrasonic connection with the voltage supply member is performed by using the elongated connecting portion formed integrally with the thin electrode plate, the necessary portion for connection is reduced by half. In addition, the number of assembling steps can be reduced, and the assembling time can be further reduced. In addition, the amount of protrusion from the peripheral surface of the ultrasonic motor is also reduced only by the sum of the thickness of the voltage supply member and the thickness of the thin electrode plate. Thus, since the amount of protrusion from the peripheral surface of the ultrasonic motor is very small,
The motor can be further downsized. Since the distance required for connection is reduced and the number of connection points is also reduced, the cost of assembling the motor is reduced and the reliability of the motor is improved.

[0056]

As described above, according to the present invention, it is possible to provide an ultrasonic motor having a small space and capable of improving efficiency by increasing the vibration amplitude.

[Brief description of the drawings]

FIG. 1 is a side view showing an entire ultrasonic motor of a first embodiment of the present invention in which a right half from a center axis is shown in a cross section.

FIG. 2 is an exploded perspective view showing the stacked piezoelectric elements of the first embodiment, which are stretched in a central axis direction.

FIG. 3 is a cross-sectional view of the right half of the first resonator, showing a state where the ultrasonic vibrator of the first embodiment undergoes bending vibration.

FIG. 4 is a diagram showing the relationship between the thickness of the flange portion and the vibration amplitude in the first embodiment.

FIG. 5 is a plan view of an ultrasonic transducer according to a second embodiment of the present invention, and a side view showing a cross section of a right half from a central axis.

FIG. 6 is a side view of an ultrasonic transducer according to a third embodiment of the present invention, showing a half of the center axis from a cross section.

FIG. 7 is a sectional view showing a right half of an ultrasonic transducer according to another example of the third embodiment.

FIG. 8 is a side view showing a right half of an ultrasonic motor according to a fourth embodiment of the present invention in cross section.

FIG. 9 is an exploded perspective view showing the piezoelectric element and the thin electrode plate of the fourth embodiment stretched in the central axis direction.

FIG. 10 is a partial perspective view schematically showing a connection between a voltage supply member and a thin electrode plate according to the fourth embodiment.

FIG. 11 is an enlarged sectional view showing a connecting portion of the fourth embodiment.

FIG. 12 is an enlarged perspective view showing a connection portion between a flexible substrate and a thin electrode plate according to a fifth embodiment of the present invention.

FIG. 13 is an enlarged perspective view showing a voltage supply member and a connection part of a thin electrode plate according to a modification of the fifth embodiment.

FIG. 14 is an enlarged perspective view illustrating a voltage supply member and a connection portion of a thin electrode plate according to a sixth embodiment of the present invention.

FIG. 15 is an enlarged perspective view showing a connection portion between a flexible board and a thin electrode plate according to a seventh embodiment of the present invention.

FIG. 16 is a perspective view showing the shape of a thin electrode plate according to the seventh embodiment.

FIG. 17 is an enlarged sectional view showing a connection portion between the flexible substrate and the thin electrode plate according to the seventh embodiment.

[Explanation of symbols]

1, 2, 3, 4 Piezoelectric element (electrical-mechanical energy conversion element) 13 Rotor (driven member) 16 Flange part 20 Disc spring (pressing member) 23 Vibrating piece 24 Vibration generating part

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-113569 (JP, A) JP-A-6-178561 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02N 2/00

Claims (3)

(57) [Claims] 1. A rod-shaped electric - mechanical energy conversion element
And an electric signal is applied to the electro-mechanical energy conversion element.
A vibration generating part that rotates by tilting the end face with respect to the central axis by applying the vibration , and a coaxially provided adjacent to one end face of the vibration generating part .
Which is formed in the connecting portion of the resonator element having a groove on a side surface, and the resonator element and the vibration generating portion, the
The resonance frequency of the vibration generator and the resonance frequency of
A flange portion forming a matching shape, is pressed against the vibrating element, an ultrasonic motor, characterized by comprising a driven member, a to be moved in a predetermined direction. 2. A rod-shaped electro-mechanical energy conversion element.
And an electric signal is applied to the electro-mechanical energy conversion element.
The end face turns while tilting with respect to the center axis.
A vibration generating portion that performs a rolling motion, and is provided coaxially adjacent to one end face of the vibration generating portion.
With a groove on the side that is divided into multiple parts around the axis.
Vibrating reed, and a fan formed at a connecting portion between the vibrating reed and the vibration generating section.
A flange portion and a driven portion pressed by the vibrating piece and moved in a predetermined direction.
Ultrasonic motor, characterized in that equipped with wood, a. 3. A rod-shaped electro-mechanical energy conversion element.
And an electric signal is applied to the electro-mechanical energy conversion element.
The end face turns while tilting with respect to the center axis.
A vibration generating portion that performs a rolling motion, and is provided coaxially adjacent to one end face of the vibration generating portion.
A vibrating reed having a groove on a side face, and a connecting portion between the vibrating reed and the vibration generating section,
Both the plane parallel to the central axis and the plane perpendicular to the central axis are formed thin.
And a driven portion that is pressed by the vibrating reed and is moved in a predetermined direction.
Ultrasonic motor, characterized in that equipped with wood, a.